A light emitting diode (LED), a type of semiconductor light emitting device, is a semiconductor device capable of generating light of various colors according to the recombination of electrons and holes. Compared with a filament-based light emitting device, the semiconductor light emitting device has various advantages such as a long lifespan, low power consumption, excellent initial driving characteristics, high vibration resistance, and the like, and thus, demand for the semiconductor light emitting device continues to grow. In particular, recently, a Group III-nitride semiconductor capable of emitting short-wavelength blue light has come to prominence. However, nitride semiconductors experience efficiency droop, in which quantum efficiency is degraded as injection current density is increased. Thus, in the art, a method for enhancing quantum efficiency of a semiconductor light emitting device is required.